Screw clamp



Feb. 1,1927.

G. ROBERTS ETAL scREw CLAMP Filed Nov. 27, l1925 A Naldi/1' Ro auf ,turning sai Patented Feb. 1, 1927.

GLEN `EOBER'rs AND lirancrlniius'nYsrHE, or MINNEAPOLIS, MINNESOTA.

l scaEw CLAMP.

Application mea November 27, 1925. serial No. 71,6'5.

Our present invention has for its object to provide a simple and highlyelicient screw clamp intended for general use, but especially adaptedfor detachably securing interchangeably usable screen and glass panelson doors, and of the type disclosed and claimed in our two pending U. S.applications, one of which was -filed March 24, 1924 under Serial Number701,421, and the other of which was filed December 19, 1924 under SerialNumber 756,947.

To the above end, generally stated, th invention consists of the noveldevices and combinations ot devices hereinafter described and defined inthe claim.

In the accompanying drawings, which il lustrate the invention, likecharacters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a. front elevation of adoor having a removable screen panelheld in position by a plurality of the improved screw clamps;

Fig. 2 is a fragmentary inside elevation o the door, screen anel and oneof the screw clamps, on an en arged scale;

Fig. 3 is a detailview in section, takenon the line 3 3 of Fig. 2; y

Fig. 4 is a view principally in elevation showing the members of one ofthe screw clamps separated;

Fig. 5 is' a fragmentary detail view partly in elevation and partly insection showing, on an enlarged scale, the headed screw and therespective head member loosely applied thereto; andv l Fig. 6 is a viewcorresponding to Fig. 5, but'illustrating the head member rigidlysecured to the headed screw.

I In the drawings, there is illustrated a door 7 .of the type havinginterchangeably usable screen and glass panels, the former 4of which islshown andv indicated by the numeral 8. The outer edge portion of thepanel 8 is rabbeted at 9 and mounted in a rabbeted seat 10 in the outer:tace of the door 7 Said screen panel 8 is removably h'eld in place by aplurality (as shown tour) of the improved screw clamps. 4

Each screw clamp comprises two disc-like head members 11 and 12, and ascrew 13 4having a head 14 the under side ofl which is beveled andin thetop of which is a channel 15 for the a plication of a screw driver forscrew. The outer faceof the .head member 11 is convex 'and which headmember has integrally formed with its back or inner face an axiallyprojecting sleevelike body 16l having an internal :screw thread 17 andwhich body is applied Ito the .screw 13 as a nut. The .outer end .of thesleeveflike Cut and pressed from the peripheral edge portion of the headmember 11 is .a plurality of inwardly projecting lugs 1S for holdingsaid head member from turning at the time the screw 13 is appliedthereto.

The headed screw 13 has a short unthreaded portion 19, just under itsvhead 14, of a diameter slightly less than that of the diam-v eter otthe'thread 20 on said -screw. The screw thread 20 'is formed by pressingthe same from the body of the headed screw 13, the original diameter ofwhich was the same as that of the unthreaded portion 19. By thus formingthe screw thread 20, thc same is pressed outward of the originaldiameterv of the body of the headed screw'13 thereby giving the 4same anexternal diameter greater than that of the unthreaded portion 19 of saidscrew. The head member 12 is provided with an axial bore 21 of suchdiameter as to permit said head member to be moved axially over thescrew thread 2O and be positioned around the Unthreaded portion of theheaded screw 13.- In the outer face of the head member 12 is acountersunk seat 22 for the screw head 14. The outer face ot the headmember 12 is beveled from its countersunk seat 22 to its periphery.

After the head member 12 is positioned onto the headed screw 13 with itshead 14 in the countersunk seat 22, an annular groove- 23 is pressedinto the inner face of said head member. just outward of and concentricwith its bore 21, to displace or contract the stock of the head member12 at the bore 21 onto the unthreaded portion 19 of said screw and to adiameter less than that of the screw thread 20. as shown in Fia. 6, tohold the head member 12 on the hea ded screw 13.

1n applying the screw clamp to the door-7. aV hole 24 is bored into theouter face of said door to receive the sleev'e-like'body 16 of the headmember 11'and permit the inner face ot' said head member to beardirectlyon said door'. A relatively small bore .25, axially alignedwithl the bore 24 is bored the rest of the way through the door 7 toreceive the headed screw 13 which is screwed into the sleeve-like body16 with the head member body 16 is closed by the head member 11. V

to clamp the head members 11 and 12 against' opposite sides of the door7 and with the head member 12 overlapping and bearing against the frameof the screen panel 8, said panel will be securely but detachablysecured to the door 7. lVhen turningr the screw 13 into the body 16 withthe head member| 12 pressed against the door 7 and frame of the panel 8,said head member will be held by friction from turning, but theconnection between the head member 12 and screw 13 is such as to permitthe screw to turn in respent to said headmember. By contracting thestock of the head member 12 at its bore 21 into the unthreaded portion19 of the screw 13 and back of the screw thread 20, said head member andscrew are connected in assembled relation.

What we claim is: v

A screw clamp comprising two head members and a headed screw, one ofsaid head members having an internally screwlthreaded sleeve-like bodyapplied to. said screw.l said screw having at the under side of its heada short unthreaded portion of a diameter less than that ofthe thread onsaid screw, the other of said head members having a bore through whichthe headed screw projects and which headmember at its bore surrounds theunthreaded portion of the headed screw and has a countersunk seat inwhich the head of said screw is mounted, the stock surrunding the boreinthe last noted head member being upset onto the unthreaded GLEN ROBERTS.MARTINUS DYSTHE.

